Free-flying toy with propeller drive



Se t. 6, 1960 r H. BRoss 2,951,313

FREE-FLYING TOY wna PROPELLER DRIVE Filed April 23, 1957 2 Sheets-Sheet1 )1 INVEN elmut Brass Sept. 6, 1960 H. BRoss 2,951,313

FREE-FLYING TOY wm-x PROPELLER DRIVE Filed April 23, 1957 i Y 2 Sheets-Shee tz ./N VE/v TOR Heimut Brass FREE-FLYING TOY WITH PROPELLERDRIVE Helmut Bross, Hannover, Germany. (40 Weichselgarten Strasse,Albenberg-Nurnberg, Bavaria, Germany) Filed Apr. 23, 1957, Ser. No.654,568

Claims. (Cl. 46-44) The invent-ion relates to a free-flying toy withpropeller drive, the driving power of which is supplied, not as hithertoby a clockwork mechanism, a small rubber motor or the like, but by anair current which is blown against the propeller for a short time. Thenew method of drive is extremely simple, a fact which is of greatimportance for manufacturing toys in mass production, and the toy istherefore cheap to produce and enables surprising effects to beobtained, which were not possible with the known driving arrangementsunder similar conditions.

According to the fundamental idea of the invention, the propeller or thepart of the toy carrying it, is so arranged or the whole toy is soconstructed that the propeller or the part carrying it or the entire toyis not propelled by the air current blowing against it, but that, afterthe current of air is stopped or interrupted, and after the propellerhas attained a sufiiciently high speed of rotation, the propeller, whilecontinuing to rotate, has an air foil which generates an air current thepower effect of which, at least at the beginning, is greater than halfthe specific weight of the flying toy, so that a flying 'movement takesplace.

The propeller is preferably given a diameter which correspondssubstantially in size to the diameter of the driving air current. Fortoys, the propeller of which is rotated by air blown from the mouth, ithas been found advantageous to make the diameter of the propellersmaller than 5 cms., because a free blast air current produced with themouth has, at a distance of about 30 cms., a diameter of only about 3 to4 cms., as experience has shown. For obtaining a maximum degree ofefficiency, the propeller diameter should not be greater than the meandiameter of the blast air current.

The propeller, fitted on the toy, is caused to rotate by a free blast ofair produced, for example, directly with the mouth and, after the blastis stopped, the toy is Patent propelled in the opposite direction to theblast by a reverse propeller action. It has been found that, in order toattain a satisfactory degree of efficiency both when blowing against thepropeller and also when the propeller continues to run after the blastceases to act and translates the stored up energy into propelling force,it is advantageous to make the propeller in trefoil shape with propellerblades increasing in width in outward direction and formed by flatsurfaces set at an angle to the plane of rotation.

In a simple form of construction to demonstrate the theory of operation,the toy consists of a propeller with a hub and a rod-shaped startingholder which latter is provided with a free stub axle onto which thepropeller can be slipped so that it can rotate freely. The startingholder may, however, also be constructed as a handle with an axlemounted thereon so that it can rotate freely and provided on its freeend with a coupling member for establishing a rotary connection with thepropeller.

In order to increase the attraction of the toy, it can, according to amodified form of construction, be made in 2,951,313 Patented Sept. s,1960 the form of a helicopter comprising a fuselage with anundercarriage and a propeller. This toy can beprovided on its supportingpoints of the undercarriage with suitable frictional materials or pointswhich hold the toy when it is being blown upon. Preferably, however, theflying toy is provided with a special starting holder, e.g in the formof a small airfield which, according to the arrangement of thesupporting points of the undercarriage of the toy, has depressions whichare shaped in such a manner thatthey prevent the toy helicopter fromveering sideways and falling over. 7

According to another proposal, the toy can also be made in the form of arigid-winged aircraft for horizontal flight comprising a fuselage, apropeller rotatably mounted between two collars, rotatable runnerwheels, and locking means preventing the toy aircraft from movingbackwards. If said aircraft is blown upon from the front it will, whenthe blast ceases to act, move forwards in counter-direction to the blastand, provided the propeller is brought to a suificiently high speed ofrotation, carry out flights over short distances. The locking means can,in combination with a rough supporting surface, such as a tablecloth orthe like, consist of a rearwardly inclined point which digs into thesupporting surface. However, in order to prevent the aircraft frommoving backwards when exposed to the blast, it can also be provided witha special starting holder.

The starting holder for the rigid-winged aircraft has an abutment whichprevents the aircraft from running backwards and abutments which holddown the aircraft on the starting holder when subjected to blast andprevent the aircraft from bucking yet do not prevent the subsequentforward movement thereof. So as to *exclude the possibility of thefuselage turning with the blades about the axle of the propeller underbearing friction, owing to the light weight of the propeller and thefuselage, it is advisable to provide the rigid-winged toy aircraft withwings set in I-shape.

In a preferred form of construction of the invention, a starting holderis provided both for the helicopter and also for the rigid-wingedaircraft, in the form of a stand, airfield or a transportable startingframe which is provided with a suitably arranged nozzle from which anair current is directed on to the propeller. The nozzle can be connectedby an air conduit, which may be in the form of a tube or hose, to amouthpiece for blowing. To prevent the formation of eddy currents, acurved guide wall is preferably fitted in a curved section or the airconduit.

The propeller can be operated by an air current produced by the mouthor, under greater pressure, by an air compressing device, such as a pumpor pressball. Propeller and aircraft must then be constructed to conformwith the different conditions resulting from the stronger air blast anddimensioned in accordance with actual requirements.

In a further development of the idea according to the invention, thestarting holder and blowing device may be made in form of an airfieldwhich can be so constructed that it incorporates a possibility for thetake-01f of a toy helicopter or rigid-winged aircraft. In this caseeither a common air conduit may be provided which can be selectivelyswitched over from one to the other of two nozzles or a separate airconduit, if necessary capable of being switched on and off, can beprovided for each nozzle.

Several preferred embodiments of the invention are illustrated byway ofexample in the accompanying drawings, in which I Fig. 1 is anelevational view of a simplified flying toy illustrating the theory ofoperation and comprising .a starting holder and a propeller;

Fig. 2 is a perspective view of the propeller shown in Fig. 1;

Fig. 3 is a side elevational view of a toy helicopter comprising afuselage, an undercarriage and a propeller, for which a separatestarting holder is provided;

Fig. 4 is a front elevational view of a toy comprising a toy helicopterand an airfield stand with a nozzle fitted near the top of a structureon the stand for directing an air current onto the propeller andcooperating with a compressible ball drive for producing the aircurrent;

Fig. 5 is a side elevation of a toy rigid-winged aircraft placed on anairfield with a nozzle and pressure ball drive arranged in the airfield;

Fig. 6 is a cross section on line VI--VI of Fig. 5;

Fig. 7 shows an arrangement similar to Fig. 5, partly in section, forair blast drive;

Fig. 8 shows in perspective view a toy aircraft of the type illustratedin Fig. 7 which is separated from the starting holder incorporating theblower tube, and

Fig. 9 is a perspective view, .partly in section, of the starting holdershown in Fig. 7.

In Fig. 1, 1 designates a starting holder consisting of a rod-shapedhandle and 2 a stub axle mounted on the starting holder, onto which axlea propeller 3, which is provided with a hub and in Fig. 2 is shown as oftrefoil shape, is loosely slipped until the propeller hub bears againstthe starting holder, and on which the propeller is freely rotatable. Thepropeller has blades which are formed from flat material widening inoutward direction and set at a suitable angle in relation to the planeof rotation. The propeller is caused to rotate at a high speed, forexample by blowing with the mouth. When the current of air blown in thedirection indicated by arrows 4 is stopped, the propeller, provided ithas attained a snfliciently high speed of rotation, rises into the air.

Diflfering from the example illustrated in Fig. l, the starting holder 1can also consist of a tube into which a central stub axle on thepropeller can be introduced.

In the form of construction illustrated by way of example in Fig. 3, thepropeller 3 is rotatably mounted on a stub axle 6 mounted in verticalposition on the fuselage of a toy helicopter 5. A collar 7 prevents thepropeller 3 from separating from. the stub axle 6. The flying toy isplaced on a starting holder 10 so that at least three supporting points,for example wheels 8, engage in suitably shaped recesses 9 in thestarting holder, which represents, for example, an airfield. Therecesses 9 are so dimensioned and so shaped that they prevent theaircraft from slipping out sideways during the blowing operation.

Fig. 4 shows a toy, also in the form of a helicopter, with a propeller 3freely rotatable about a vertical stub axle 6 on the helicopter 5 andheld on the stub axle by a collar 7. The toy helicopter is placed, as inthe example illustrated in Fig. 3, on a starting holder 11 representingan airfield, provided with recesses 9. At the upper end of a structure12 representing a building or a tower on the airfield, a nozzle 13 isfitted at an incline directed towards the propeller 3 of the helicopter5 placed on the airfield. The nozzle is connected by a flexible conduit14 to a pressure ball 15 which has a valve aperture 16 which can becovered with the thumb. The axis of the nozzle is so inclined to theplane of rotation of the propeller 3 that the structure 12 will notimpede the takeoff of the helicopter as soon as the propeller 3 has beenbrought to the speed of rotation necessary for producing the flyingmovement by means of the air current produced by the pressure ball 15,and this air current has been interrupted.

In Fig. 5, 17 designates a rigid-winged aircraft for horizontal flightwith a freely rotatable propeller 3 and V-shaped wings 17a on a fuselageconsisting of a thin vertical plate mounted on two wheels 21.

An airfield 18 serves as starting holder and has an abutment 19 againstwhich the tail end of the aircraft fuselage bears so that the aircraftis prevented from moving backwards in the direction of the air currentduring the blowing operation. When the propeller is subjected to theblast, the aircraft is secured against bucking by angular abutments 20,the horizontal arms of which engage the wheels 21 from above, as isclearly shown in Fig. 6. A nozzle 22 is formed in the airfield 18 andthrough this nozzle a free air current is directed against the propeller3 of the aircraft held in starting position. The axis of the nozzleforms an obtuse angle with the axis of rotation of the propeller and thenozzle is connected up with a pressure ball 23 provided with a valveaperture 24 which can be covered with the thumb.

Instead of the pressure balls 15 and 23, air pumps or other suitable aircompressing devices can be provided, and, in the case of smaller toysfor which a less powerful air current is suflicient to impart to thepropeller 3 the speed of rotation necessary for producing the flightmovement, a blowing mouthpiece can be pro vided for the forms ofconstruction illustrated by Way of example in Figs. 4 and 5. Fig. 7shows an example of this construction.

In Fig. 7 the starting holder consists of a blow tube 25 one end ofwhich is bent back through an angle of almost and provided with a nozzle26. A guide surface 27, fitted or formed in the bend of the blow tube 25and bent almost in semicircular shape, serves to prevent the formationof eddy currents in the air current passing through the tube bend. Onthe upper side of the blow tube 25 a plate 29 is fixed on a bracket 28at an incline rising towards the nozzle 26 and provided with acontinuous longitudinal aperture 30 which is open on its full width onthe end directed towards the nozzle 26 whereas it is closed on the otherend by rising side walls 29a at the edge sections (see Fig 9). A wallportion 29b of the plate closing the upper side of the aperture 30 isprovided with a slot '31 extending the entire length of the plate andthe boundary edges of this slot are flush with the inner edges of therising walls 29a.

The upper part of the aircraft fuselage and the wings are made from aplate 32 of plastic material or the like, the side sections of which arebent up to form wings 32a standing in V-shape. The section of the plate32 forming the tail end 3212 is also bent upwards. On the underside ofthe middle section of the plate 32, a body 33 of plastic material or thelike, of U-shape in side elevation and of T-shape in front elevation, isfixed by rivets 34, by welding or other suitable means. In bores in twobrackets 33a of the body 33 which constitutes the main part of theaircraft fuselage, an axle 35 is mounted so that it can rotate freelyand secured against axial displacement by collars 36. The rotary axle 35has a thickened, square front end 35a on which the propeller 3 is fixed.

The aperture 30 and the slot 31 in the plate 29 are shaped to correspondto the T-profile of the body 33 so that the latter can be slippedtherein until it comes into contact with the transverse wall 29a. Inthis manner the toy is hold while air is being blown on it through theblow tube 25. When this blast of air is interrupted, the aircraft willbe moved forwards by the rotating propeller, the body '33 becomesdetached from the holding plate 29 and the flying toy rises into theair. The V-position of the wings 32a prevents the aircraft fuselage fromfollowing the turning movement of the propeller due to bearing frictionwhile the aircraft is in flight. For this same purpose V-shaped wingsare also provided for the toy aircraft in the form of constructionillustrated in Fig. 5.

From the above detailed description of the invention, it is believedthat the construction will at once be apparent, and while there areherein shown and described preferred embodiments of the invention, it isnevertheless to be understood that minor changes may be made thereinwithout departing from the spirit and scope of the invention as claimed.

I claim:

1. A free flying toy comprising an aircraft body, a propeller rotatablymounted on the body, a starting holder on which the toy is supported,means for directing a shorttimed air blast stream in a direction towardsthe propeller opposite to the direction of flight with the propellerproducing a lifting force, the reaction force of said lifting force atthe take-off corresponding to more than half the specific weight of thetoy, said aircraft body being in the form of a rigid-winged aircraftcapable of flying and comprising a fuselage, the starting holder havingan abutment engaged with the fuselage for preventing the fuselage frommoving backwards when in starting position and at least one abutmentpreventing the aircraft from rearing when subjected to the blowingoperation without interfering with the subsequent forward movement ofthe aircraft.

2. A flying toy comprising a fuselage, a propeller journaled for freerotation on said fuselage and having an air foil developing suflicientlift upon a predetermined speed of rotation of said propeller to makethe fuselage air borne in a predetermined direction of flight, fuselageholding means removably retaining said fuselage thereon and includingmeans permitting movement of said fuse lage only in said predetermineddirection of flight due to rotation of said propeller at saidpredetermined speed, and fluid pressure means directed toward the axisof rotation of said propeller and in a plane in advance of and out ofthe path of flight of said fuselage, said fluid pressure means havingsuflicient force to impart an inertial speed of rotation to saidpropeller at least equal to said predetermined speed whereby saidfuselage becomes air borne upon cessation of said fluid pressure, saidair foil producing a reactive force more than one-half the specificweight of said toy.

3. The structure of claim 2; said fluid pressure means comprising adischarge nozzle connected to said fuselage holding means and beingdirected toward the axis of rotation of said propeller.

4. The structure of claim 3; said discharge nozzle comprising an orallyengageable tube, the fuselage holding means being mounted on said tube,said tube including a reverse curved end portion directed toward saidfuselage holding means.

5. The structure of claim 2; said fuselage holding means including anabutment portion conforming to a portion of said toy.

References Cited in the file of this patent UNITED STATES PATENTS1,359,406 McCarty Nov. 16, 1920 1,383,795 Fowler July 5, 1921 1,613,982Cohn Jan. 11, 1927 2,119,133 Hogan May 13, 1938 2,198,509 Burke Apr. 23,1940 2,731,769 Holt Jan. 24, 1956

